Hi all . I've had 4 discus for the last 3 to 4 months and have just added another . The problem is the calmest discus in the tank has gone really aggresive towards the new one and has it pushed up into a corner and wont let it out . will the aggression back off after a while ? Or have i wasted money on a fish that wont be seen 90% of the time ? :-(

1077

12-07-2011 02:13 AM

Is the new fish smaller than the other's? If so,, it may just be the unfortunate victim until pecking order is eastablished as with most large cichlid's.(Give it a few day's)
You may, if you have another tank or tub available,, pull the aggressor out for a day or two and then re-introduce the fish after you have moved decor around a bit.
Could also give the new fish a break, by placing a couple clay pot's large enough for the fish to enter, in the tank.This would give fish, or fishes a place to retire to if thing's get too rough.(Or large driftwood piece)
Ultimately,, If thing's get too bad and damage is occuring, and or fish is not able to feed as the other's do,, it may be neccesssary to re-home the fish being picked on.IMHO

DiscusFan

12-07-2011 04:28 AM

Hi . Thanks . The new fish is the same size if not a little bigger than the aggresive fish . But i have noticed that he is starting to pick on the others as well . Nearly looks like he has decided to become the boss of the tank .

The tank has plenty of drift wood with plants for the others to hide in . Just seems funny that the calmest fish has turned into the most aggresive in the tank in a matter of 2 to 3 days .

Byron

12-07-2011 12:57 PM

With discus as with angelfish, the group intended for the aquarium should be acquired at the same time (a couple of days at most between fish). Adding a new fish after the initial group has become accustomed to the tank is always a risk. Trouble may or may not occur, but it is possible and usually probable that it will. As you have witnessed.

As 1077 indicated, this is the fish establishing their "pecking order." All cichlids do this, and many other non-cichlids do as well. Various things can bring out aggressive traits in a cichlid. The advice from 1077 to remove the newcomer and rearrange things, then re-introduce it, can sometimes work. If any fish is continually being picked on, this is highly stressful for that fish and if it continues will usually cause health problems and even death.

I agree with 1077 to carefully observe things for a time; sit in front of the tank for an hour or more several times to get a good idea of what is occurring when the fish are "on their own."

Byron.

DiscusFan

12-07-2011 05:27 PM

Thanks Byron . I sat and watched the tank for 3 to 4 hours yesterday . The biggest thing i have noticed with the aggression is that their is no injuries or damage to any of the discus . The new discus (red turquoise) is looking pretty calm so far . Just keeps getting pushed back into one corner .

Wish i had of had enough cash at the time to get all fish at once . Another learning experience .